The present invention is directed to conveyor belt cleaning apparatus and more specifically to a tensioning assembly for maintaining close contact between a scraper blade of a conveyor belt cleaning apparatus and a conveyor belt of a belt conveyor machine. Belt conveyor machines are commonly used in the construction and mining industries to transport loose bulk material, such as sand, gravel, concrete, asphalt, coal, ore, waste, earth, etc. As the moisture content of the bulk material increases, there is a tendency for some of the material to stick to the conveyor belt. Conveyor belt cleaning apparatus typically comprise a scraper blade mounted on a pivotable shaft that is turn pivotably mounted near the return belt pulley of the conveyor machine. A tensioning mechanism associated with the shaft biases the scraper blade toward the conveyor belt to remove material from the belt before the return travel of the belt. Due to the abrasive nature of the bulk material being transported, over time the portion of the scraper blade in contact with the conveyor belt wears. The tensioning mechanism automatically adjusts the shaft as the scraper blade wears to keep the scraper blade adequately in contact with the conveyor belt to perform the belt cleaning function. Periodically, the belt cleaning apparatus requires servicing. There is a need for an improved tensioning mechanism for a belt cleaning apparatus that is easy to install and remove from the belt conveyor machine.